土工格栅加筋石灰黄土强度和刚度特性试验研究

为处理黄土地区桥头跳车问题,文中提出采用土工格栅加筋石灰黄土填筑桥头路堤的方案,首先对石灰黄土完成三轴试验,确定了合适的石灰掺量;然后采用无侧限抗压试验和回弹模量试验分别对土工格栅加筋石灰黄土的强度和刚度特性进行研究,着重研究强度和刚度的主要影响因素及其影响规律。通过对比分析试验结果,得出以下结论:①对于文中采用的黄土,当采用石灰进行稳定时,经济合理的石灰掺量为5%~7%。②采用土工格栅加筋的石灰黄土与纯黄土相比,其抗压强度与回弹模量均有显著提高。③试件中的加筋层数越多(即加筋层间距越小)时,土工格栅加筋石灰黄土的抗压强度与回弹模量越大。当加筋层数达到一个较高值后,再增加格栅层数对抗压强度的提升较小。

Experimental Study on Strength and Stiffness Characteristics of Geogrid Reinforced Lime Stabilized Loess

In order to control the vehicle bumping at bridge head in the loess area,a programme is made to fill the embankment at the bridge head with geogrid reinforced lime stabilized loess.Triaxial test is first performed on the limestabilized loess,the appropriate lime dosage is analyzed and determined,and then the unconfined compression test and the rebound modulus test are used to reinforce the geogrid reinforced limestabilized loess,respectively.The strength and stiffness characteristics are studied,and the main influencing factors of strength and stiffness and their influence laws are studied.A detailed comparative analysis of the test results leads to the following main conclusions:①For the loess used in this paper,when lime is used for stabilization,the economical and reasonable lime dosage is 5%~7%.②Compared with pure loess,the geogrid-reinforced limestabilized loess has significantly improved compressive strength and rebound modulus.③The more layers of geogrid-reinforced lime stabilized loess,the greater its compressive strength and rebound modulus.After reaching a certain number of layers,increasing the number of layers to improve the compression strength is small.